Leishmania donovani donovani and Leishmania donovani chagasi as antigens in a direct agglutination assay for the diagnosis of kala-azar

RESUMO

The need for a reliable method for the immunological diagnosis of Kala-azar is imperative. Leishmania donovani donovani and L. donovani chagasi culture promastigotes were compared as antigens in a direct agglutination test (DAT) for the diagnosis of visceral leishmaniasis in Brazil. Both antigens were successfully employed for the DAT, Showing 100½ sensitivity and > 98% specificity when used to test sera from Brasilian and African Kala-azar, Chagas'disease, malaria, filaria and symphilis patients, and on sera from Brazilian controls. Cross-reactions were sometimes observed when cutaneous and cucocutaneous leishmaniasis patient sera were teste. The vross-reactions were completely abolished by the addition of 0.78% 2-mercaptoethanol to the serum diluent. These data show data that this improved Dat can be used for the diagnosis of visceral leishmaniasis in Brazil